The present invention generally relates to an encoder, a system and a method for outputting a signal. More specifically, the present invention relates to an encoder and a system which detects light emitting from a light emitting element with a light detector to output a signal.
The encoder and the system may have a housing. A light emitting element, a light detector and/or a rotor may be within the housing. The light detector may detect light from the light emitting element. A light pipe may transmit and/or may deflect light from the light emitting element in the housing.
The rotor may cooperate with the shaft. Rotation of the shaft may rotate the rotor to block, to deflect and/or to absorb light from the light emitting element. The light detector may detect movement and/or a position of the shaft. The shaft may rotate to move a sprocket which may contact a spring. A cable and/or terminal pins may output a signal based on the direction, the amount and/or the intensity of light. The signal may correspond to the position of the shaft. The shaft may contact a pushbutton which may contact a circuit board to output the signal via the cable and/or the terminal pins.
It is generally known to incorporate and/or to connect a switch to a device, such as, for example, a computer, a radio, a global positioning system, a television, a game system and/or the like. The switch outputs a signal to control the device. For example, the switch may output a signal to change a radio station and/or to control power supplied to the device. In another example, a user may output a signal to control a display for a global positioning system. A user may control the switch by turning and/or depressing a shaft within the switch. Movement of the shaft outputs the signal to a processing unit. The signal corresponds to a position of the shaft. The processing unit receives the signal to control the device.
More specifically, the switch contacts a circuit by, for example, an arm attached to the shaft. As the switch turns, the arm of the shaft engages one of an array of points within the circuit which are arranged around the shaft. The circuit is closed in a loop by contact with the arm of the shaft. As a result, the switch outputs a signal which corresponds to a location of the shaft. However, repeated contact between the arm of the shaft and the points of the circuit result in the switch failing to output the signal. For example, points within the circuit may chip and/or may separate from the circuit to prevent the switch from outputting the signal. In addition, the shaft of the switch may eventually rotate without the arm contacting the circuit and/or without the contact of the circuit closing the loop of the circuit. Accordingly, the operational life of the switch is limited.
It is also generally known for a user to use a magnetic switch to output a signal. The magnetic switch uses a Hall effect sensor to output a signal rather than a mechanical arm to output a signal. The magnetic switch has a magnet positioned on the shaft at a location within the switch. The user rotates the shaft to output a signal to, for example, turn a radio to an “on” position. Rotation of the shaft moves the magnet to produce changes in magnetic field density. The Hall effect-sensor detects changes in magnetic field density to output the signal corresponding to a position of the shaft.
However, movement of the shaft is limited by the locations of the Hall effect sensor. Specifically, the switch will only determine positions of the shaft where a Hall effect sensor is located. Providing multiple sensors at multiple locations within the switch is costly. In addition, multiple sensors results in a higher likelihood that the switch will fail to output the signal or output an inaccurate signal.
Further, a magnetically operated switch produces no sound, such as, a clicking noise. Still further, the magnetic switch does not provide tactile feedback to a user. As a result, a user cannot determine whether a shaft of the switch is moving and how far the shaft of the switch has moved from a previous position.
A need, therefore, exists for an encoder, a system and a method for outputting a signal. Additionally, a need exists for an encoder, a system and a method for outputting a signal which optically detects positions of a shaft. Further, a need exists for an encoder, a system and a method for outputting a signal having a shaft connected to a sprocket which contacts a spring to provide audible and tactile feedback to a user. Still further, a need exists for an encoder, a system and a method for outputting a signal having a shaft rotatable to multiple positions which may be detected by a light detector.
Moreover, a need exists for an encoder, a system and a method for outputting a signal having a shaft wherein depressing and/or pushing the shaft depresses a push button to provide tactile feedback to a user. Furthermore, a need exists for an encoder, a system and a method for outputting a signal having a shaft wherein rotating the shaft produces a sound to indicate that the shaft is rotating. In addition, a need exists for an encoder, a system and a method for outputting a signal having a single circuit board for detecting light and transmitting light within the encoder. Further, a need exists for an encoder, a system and a method for outputting a signal which provides a nearly infinite life of components of the encoder and/or the system.